Timing and Duration of Traffic-related Air Pollution Exposure and the Risk for Childhood Wheeze and Asthma

By Dr Deepu

In a study in the August 15 issue of AJRCCM, Brunst and colleagues examine the relationship between exposure to traffic-related air pollution (TRAP) and longitudinal wheezing phenotypes and asthma at age seven. The authors found that early-life exposure to TRAP is associated with increased risk for persistent wheezing, but only long-term exposure to high levels of TRAP throughout childhood was associated with asthma development. The authors state that "These findings provide new evidence that early-life exposure to high levels of TRAP sets a trajectory toward persistent wheeze and that chronic early-life exposure to high levels of TRAP may be necessary for sufficient pathophysiological changes to occur in the lungs of children leading to asthma development. A strategy of prevention or intervention during this critical time period may be able to interrupt this chain of events."